Hydrochloric Acid → HCID 13457933, compound

Participants

Reaction Steps

A solution of cis-1,3,4,6,7,11b-hexahydro-2-methyl-7-(4-nitrophenyl)-2H-pyrazino[2,1-a)isoquinoline (5.2 g, 0.014 m) in methanol (500 ml), water (100 ml) and conc HCl (5 ml) was hydrogenated on a Parr apparatus over 2.0 g of palladium on carbon catalyst of 40 psi for 1 hour. The catalyst was removed by filtration and the solvents evaporated to a solid residue. This was dissolved in water (500 ml), basified to pH 11 with 50% NaOH, and extracted with ether (3×200 ml). The extracts were dried over MgSO4 and evaporated to an oil, 4.04 g. This crude product was purified by chromatography on silica gel with a Prep 500 HPLC, eluting with 2% ammoniated methanol/chloroform. Pure fractions were combined and evaporated to give an oil, 1.12 g. This was dissolved in methanol (30 ml) and acidified with HCl gas. Upon standing, a white solid crystallized, which was collected by filtration and vacuum dried at 95% for 24 hours to give 1.08 g of cis-1,3,4,6,7,11b-hexahydro-2-methyl-7-(4-aminophenyl)-2H-pyrazino[2,1-a]isoquinoline dihydrochloride, m.p. 274°-276°.

Provenance & Evidence